Piston



Dec. 19, 1922. 1,439,109.

. P. H. KUHN.

PlsToN. FILED MAY 9.1921.

INVENTOR To. alleolmm itmay concern Patented Dee. lil, i922?.

PRESTON H. KUHN, .onisnii'rrnnywesninemon.. i i

n a ienne Prs'roni Be ;;t vknown .that 1I, .PniisroN HLKUHN, i citizen ofthe. United yltntes, residing et Seattle, inthe coi'mtyoffling :indgStete of v Vitashington, have invented e certain.new`

and useful `improvement in Pistons,` of which the following ist)J specificzition-`v p This invention relates to improvementsin pistonsfor internal combustion engines and the object` of this improvement is to provide e piston having 4resilient cushion .ineens interposed betweenthe heed or thrust receiv-` permitting the y.fuel chergeto be more highly y compressed.v und, bv reason of such greater compression to develop more power.

it@ further object is to provide e piston having the portion that` inbove fthe trainsverse connecting rod pin mede in tivo parts that ere yieldingly supported in 'spaced spart relation in such :i manner es to "form :innir cushiontherebetween. 'v

`A still further object is to provide ineens for admitting air into the space between the two parts ofthe piston--wlien the piston is et the lowermost limit of its stroke thus insuringthet therewill always be an air cushion to absorb the shock when an explosion occurs. With the'ebove and other objectsin view :is Will. be apparent from the followingl description the invention `consists in the novel construction, adaptation :ind combination of parts of :i piston Jfor :in internal combustion engine es will be more clearly hereinafter described end claimed. l

ln the accompanying; dreWin; .;'s, Figure `l .is n view in elevation of :i piston constructed in accordance with this invention, 'n portion ofthe 'cylinder within which the piston is disposed being shown in cross section :1nd

the piston beingy shown et 'the limit of its upward movement in the cylinder; 2 is a view in vertical mid section showing the piston at its lowerniost position in the cylinder7 and Fig 3 is n phin vieu' showing Appicationl mean/rey e, wel. ,senin ne. 14629631 the top endfthefmein"body of 'the piston as itmight eppeiir with the top'plete removed. y l .e j"

Like yreference numerals designate like pertsvthroughoutthe."sevenzil views l Yleferring `to` the Adrziwings e the .numerzil- '5 designates L` hollow piston end ,G designates ei connecting-` rod heving'its'loiver end pivl otally attechedto e. `crank shaft .7 r and lits' upper end pivotelly attehedto etrensv'erse pin 8 in the piston.I l l rlhis invention residesin providing upon the upper end ofthe pistongzind "above the 4connecting` rod Ipivot pin 8,e` separate ,end

section 10i-het is norniellyspaced fromlthe e e "7o endfl of. the mem' body of thevpiston us at 1Q. and has cushion .means interposed 'in' the snidspace so that when en explosion" occurs in the upper endof n cylinder in which the kPiston 1s reciprocably disposed the end section l() `Wfill vieldslightly relative to the mein piston body' 5 thereby" absorbing ing;i

the beerin for the seine of the "strain ydue to such initial shock.` l n I lhecusliion between the section 'lO andthe.

`f imii'nbody of thejpiston anniv be formed by leefter it has been forced downwerdlyon'to the end ll `of the piston by the pressure of nn expanding ch erge. i

the `initial shock vofthe eplosion und i'elier--,

the connecting rod and' crunk shaft and i The ends of` the springs 14 are set Within shallow recesses 15 in the member l0 end in the end of the piston and lthe member l0 is secured to the end of the pistonby cen-` trally arranged pin-16 that is slidnble in the end ll of the piston and that is screwed securcl;7 into tlije iiieii'ibe1l0,'the pin 16 hevinn' :i heed 'li'` that linnts the movement of the member l() away from the end lli of the piston.

The member l0 provided ivith a piston ring 18 of the usual form and the mein pis-` ton body 5 .is provided neer the upper end with n siniiler piston ring 20. rl`he piston rings 1S und 2O are located just ebove and `just belen' the cushion space` l?. respectively und serve to prevent the air from being;`

crowded outl of the cushion before/it hes `heen compressed enough to absorb the initial impact of the explosion.

When the piston is at 'substantially the lowermost limit of? its travel the cushion space 12 will "registerwith periorations 21 that are formed in the walls of the cylinder 13 and if the air has been' crowded out of the cushion space 12 such space will again` fill with air the springs r14C serving'to lift the member 10 .as soon as pressure on such member is relieved by the `opening of an exhaust valve. I f In the operation'of this device when a charge is exploded above the upper piston member thefshocl` or blow oit' the initial explosion. is 1 largely absorbed by "the air 1 which fornisca cushion within the space A12 and' between the piston rings 18y and 20.

Thisgreatly lessens the'strain on the crank sha'iitand connecting `rod andfon the bear-v i ings for the same andy `in this 1way reduces ftheuwear and `*danger of breakage of these 25, the lfuel charge more highly and thus obtain parts. 1 v The cushioning of the initial shock of the explosion also makes it possible to compress a greater amount of power lfrom each chargethan, would be possible under a lower f compression. a

' The Aforegoing description taken in connection'f with' the accompanying drawings 'clearly disclosesthemethod of construction y and principle of operation of'this invention,

`but although Ir have illustrated and described'what I now consider to be a prey g ferredormof construction of'jtheA invention it ,will bel understood that the disclosure is inerelyy illustrative and that such changes scope ofthe claims.`

may bamade asrare within the spirit and 1. A pistonteomposeol of separable upper and lower portionsvthat are spaced apart to 1 leavea `chamberl forming an air cushion around `the periphery,` andpiston rings en# circling' each portionof vsaid piston and locatedabove and below the open peripheralr portion of said air chamber. 3. A piston composedv of separablefupper and lower end portions having parallel end surfaces that kare spaced a'slight "distance apart to form air'cushion chambers that arej open at the circumferential"portion of -said piston, and resilient means between the two lportions of said' piston forur'ging the same apart.` y y 4 yThe combination-with anr 'engine ycylinder, of a piston` reciproca'ble therein and composed' of separable n upper 'and .lower por-f 4tions* relatively movable 'and normally n spaced: apart tole'ave a chamber Jforming an' air cushion therebetween", said air lchamber i being openaround the circumference of the' `piston and airports in said 'cylinder arrangedto register with saidjchamber at thev lowermost limitofthe piston stroke.'

5. In `an engine a cylinder,.a piston dis-` posed thereinv andA composed `of `separable upper and lower Asections that are spaced apart to forni anl air chamber therebetween,

means 'for limiting rthe amount of separation' of 'said two sectionauneans interposed between lsaid two sections foriurgingthevsame apart, and' air inletports vin the "walls olf saidcylinder and arranged to register'with the air chamber' that is `formed between saidA two partswhen thefpiston is at the,outer' most limit oil? .its stroke.-

y Signed lat Seattle, vl/Vashington, this 19th day vof March, n'v .a

y rREsroNnKUHN. 

